image

1. Data representing a two-dimensional scene. A digital image is composed of pixels arranged in a rectangular array with a certain height and width. Each pixel may consist of one or more bits of information, representing the brightness of the image at that point and possibly including colour information encoded as RGB triples.

Images are usually taken from the real world via a digital camera, frame grabber or scanner.

See also image formats, image processing.

(21 Oct 1994)

2. <mathematics> The image (or range) of a function is the set of values of that function applied to all elements of its domain. So, if f : D -> C then the set f(D) = f(d) | d in D is the image of D under f. The image is a subset of C, the codomain.

(21 Oct 1994)